Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology, mostly seen in middle-aged women, with a prevalence of about 0.32% to 0.36% in China. The main manifestation is symmetrical, chronic progressive polyarthritis. Chronic inflammation and hyperplasia of the synovial membrane form vascular opacities that invade articular cartilage, subchondral bone, ligaments and tendons, resulting in destruction of articular cartilage, bone and joint capsule, eventually leading to joint deformity and loss of function. 1, morning stiffness stiffness in and around the joint for at least 1 h. Duration of disease – >6 weeks 2, arthritis in 3 or more regional joint sites The physician observed involvement of 3 of the following 14 regions (left or right proximal interphalangeal joint, metacarpophalangeal joint, wrist, elbow, knee, ankle and metatarsophalangeal joint) with concurrent soft tissue swelling or fluid accumulation (not just bone augmentation). Duration of disease ≥ 6 weeks 3, hand arthritis wrist, metacarpophalangeal or proximal interphalangeal arthritis in at least one joint swelling. Duration > – 6 weeks 4, symmetric arthritis Both joints are involved at the same time (bilateral proximal interphalangeal joints, metacarpophalangeal joints and metatarsophalangeal joints are not necessarily absolutely symmetrical when involved. Disease duration > 6 weeks 5, rheumatoid nodules The doctor observed in the bony prominence site. Subcutaneous nodules on the extensor surfaces or around the joints 6. Positive rheumatoid factor Any test proving abnormal serum rheumatoid factor levels, which has a positive rate of less than 5% in the normal population 7. Radiological changes Radiological changes typical of rheumatoid arthritis in the posterior-anterior phase of the hand and wrist: must include bone erosion or definite bone decalcification in the affected joint and its adjacent areas 4 of the above 7 items are satisfied or The diagnosis of rheumatoid arthritis can be made by meeting 4 or more of the above criteria and excluding other arthritis. Therefore, the diagnosis of rheumatoid arthritis have you noticed this criterion, perhaps you are not and was misdiagnosed.